Preparation and Application of Copolymer of Styrene and Maleic Anhydride as Surface Sizing Agent

A new type of surface sizing agent was prepared by random copolymerization of styrene and maleic anhydride with initiator of benzoyl peroxide in the medium of toluene, then the resultant complymer was precipitated, separated and modified .The structure of the copolymer of styrene and maleic anhydride was determined by mean of IR spectroscopy, the surface of the sized paper was studied by means of SEM.The copolymer of styrene and maleic anhydride is an efficient surface sizing agent which can improve the sizing degree and surface strength of the paper, sizing degree is 13s, tensile strength increases 13.5%, breaking strength increases 16.0% when the dosage of surface sizing agent is 0.5g/m2, the sizing efficiency of this surface sizing agent is satisfactory when it is used together with starch or PVA.